Get off your duff and build something!Training the hand and mind since 1982.

Tuesday, December 9, 2014

Mega Hurts

This project is a 1 Hertz reference clock signal for digital and binary clocks, some of our older projects used the 60 HZ line frequency as a clock reference, the problem with this is after the power company deregulation they no longer have a tight frequency standard, the power company use to be 60 Hz (+/- 1 HZ).
Now it's all over the place, I measured at my house anywhere from 55 to 70 HZ, no wonder my old clock was gaining and losing time.

Here is the schematic

Photos

Here is the schematic of the binary clock we use

Notice that coming off the secondary of the transformer it feed into a 4040 and divides down by 60, pin4 of the 7414 is 1 Hz.